From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BEF9DC433FE for ; Wed, 1 Dec 2021 17:02:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351663AbhLARGQ (ORCPT ); Wed, 1 Dec 2021 12:06:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53328 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238178AbhLARGM (ORCPT ); Wed, 1 Dec 2021 12:06:12 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EB314C061574; Wed, 1 Dec 2021 09:02:50 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id B01CAB82047; Wed, 1 Dec 2021 17:02:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 84061C53FCC; Wed, 1 Dec 2021 17:02:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1638378168; bh=CvHtrXfgBU4nCjU0B0+DUSu63UaEebLTtzXAzA4qmq4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RSi8vBwTLTb2mtXwaqcm1aN8fQhZZXHxwRfVIv3Ph+E+KA80w09id79HSoWdMxh52 Le083FK28TbGxOEYGbMSHTxk2sjdp40ebUWMOBZZ4McGEDNBV0CCawssYOcsYaM0qG cTyMKkw9UX17F3DG7cc5qHLBbPXtGm4oa2q3ex6HUWHd7IP/yRFypKJQfxTKkhsl4M O5Nz/iDP0+6EUK2mnTmAOoIKBKACBTUooxsJX8TzlAVxgS4aBBCnd4a33nF+5H8fGS mTG5ucT7w1HynJIwfHZhg7pk9b2haywLl+H4vMJGZaJfHZ4Wnou80e1ZWGDkUEVAh4 0fjdkTRY9HnNQ== Date: Wed, 1 Dec 2021 17:02:38 +0000 From: Mark Brown To: "H. Nikolaus Schaller" Cc: Paul Cercueil , Rob Herring , Mark Rutland , Thomas Bogendoerfer , Geert Uytterhoeven , Kees Cook , "Eric W. Biederman" , Miquel Raynal , David Airlie , Daniel Vetter , Neil Armstrong , Robert Foss , Laurent Pinchart , Jernej Skrabec , Harry Wentland , Sam Ravnborg , Maxime Ripard , Hans Verkuil , Liam Girdwood , Paul Boddie , devicetree@vger.kernel.org, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, letux-kernel@openphoenux.org, Jonas Karlman , dri-devel@lists.freedesktop.org, Ezequiel Garcia Subject: Re: [PATCH v10 4/8] drm/ingenic: Add dw-hdmi driver for jz4780 Message-ID: Mail-Followup-To: "H. Nikolaus Schaller" , Paul Cercueil , Rob Herring , Mark Rutland , Thomas Bogendoerfer , Geert Uytterhoeven , Kees Cook , "Eric W. Biederman" , Miquel Raynal , David Airlie , Daniel Vetter , Neil Armstrong , Robert Foss , Laurent Pinchart , Jernej Skrabec , Harry Wentland , Sam Ravnborg , Maxime Ripard , Hans Verkuil , Liam Girdwood , Paul Boddie , devicetree@vger.kernel.org, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, letux-kernel@openphoenux.org, Jonas Karlman , dri-devel@lists.freedesktop.org, Ezequiel Garcia References: <4daf0c5dbed2c47c97003ab8de0a7dbd2a335dc3.1638307601.git.hns@goldelico.com> <46070A95-0FA9-43F9-A9A9-52A7B58B88F5@goldelico.com> <58C550A4-A21E-47BA-8BAE-00B927DC7A2E@goldelico.com> <3174DA41-EB38-4C30-8752-0D9C894C74A7@goldelico.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="06/7sdeAneQqaZKj" Content-Disposition: inline In-Reply-To: <3174DA41-EB38-4C30-8752-0D9C894C74A7@goldelico.com> X-Cookie: All true wisdom is found on T-shirts. Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --06/7sdeAneQqaZKj Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Dec 01, 2021 at 05:53:03PM +0100, H. Nikolaus Schaller wrote: > > Am 01.12.2021 um 16:10 schrieb Mark Brown : > > Again, if the supply can be physically absent that is a sensible use > > case but that means completely absent, not just not software > > controllable. We can represent fixed voltage regulators just fine. > The question may be how we can know for a more generic driver that there is always a regulator. > In the present case we know the schematics but it is just one example. The datasheet will generally explicitly call out if a supply can be disconnected. In general it is astonishingly rare for this to be the case, supporting that case will tend to make designing the chip harder (you have to cope with what happens where the power domains meet) and results in whatever functionality the supplies power not working. If not otherwise specified it's safer to assume that the supplies must be connected. --06/7sdeAneQqaZKj Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmGnqq0ACgkQJNaLcl1U h9AiKgf6A1p3c1dtOyuPYAkfziLEMTL656L/Ng0sT/e9yjZ9D6KPZxQqSYqZJI2F AxQcNhi9BBM7R94mawqJ6jekuZZ0RJoVo2iPJYWJ/vM36tq01U1SeojIamTmD1LN IF4vSf9paAEB6kQGTW1WB9onUyNpaIyz358HSRZ6FzxP/9W1qVhuCgw2M16JPM5G wFd64VVU8pyBLxa8glflmm8MGFaeKBqkNFJBSnRG2kX79RRtaVeX8wN6niXIsGQp T7Uv+fFGAT+w315hhRUx10oTaZNghDPE6dYLm6SaV4fqYqhIFspHZ9GsOLPvDDvC E4+8AFtE7h0IearW001RSgvJHmQFiw== =8Z88 -----END PGP SIGNATURE----- --06/7sdeAneQqaZKj-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0C7BAC433EF for ; Wed, 1 Dec 2021 17:02:53 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D510D89F89; Wed, 1 Dec 2021 17:02:52 +0000 (UTC) X-Greylist: delayed 6738 seconds by postgrey-1.36 at gabe; Wed, 01 Dec 2021 17:02:51 UTC Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by gabe.freedesktop.org (Postfix) with ESMTPS id 42AA689F89 for ; Wed, 1 Dec 2021 17:02:51 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id B2698B82048; Wed, 1 Dec 2021 17:02:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 84061C53FCC; Wed, 1 Dec 2021 17:02:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1638378168; bh=CvHtrXfgBU4nCjU0B0+DUSu63UaEebLTtzXAzA4qmq4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RSi8vBwTLTb2mtXwaqcm1aN8fQhZZXHxwRfVIv3Ph+E+KA80w09id79HSoWdMxh52 Le083FK28TbGxOEYGbMSHTxk2sjdp40ebUWMOBZZ4McGEDNBV0CCawssYOcsYaM0qG cTyMKkw9UX17F3DG7cc5qHLBbPXtGm4oa2q3ex6HUWHd7IP/yRFypKJQfxTKkhsl4M O5Nz/iDP0+6EUK2mnTmAOoIKBKACBTUooxsJX8TzlAVxgS4aBBCnd4a33nF+5H8fGS mTG5ucT7w1HynJIwfHZhg7pk9b2haywLl+H4vMJGZaJfHZ4Wnou80e1ZWGDkUEVAh4 0fjdkTRY9HnNQ== Date: Wed, 1 Dec 2021 17:02:38 +0000 From: Mark Brown To: "H. Nikolaus Schaller" Subject: Re: [PATCH v10 4/8] drm/ingenic: Add dw-hdmi driver for jz4780 Message-ID: Mail-Followup-To: "H. Nikolaus Schaller" , Paul Cercueil , Rob Herring , Mark Rutland , Thomas Bogendoerfer , Geert Uytterhoeven , Kees Cook , "Eric W. Biederman" , Miquel Raynal , David Airlie , Daniel Vetter , Neil Armstrong , Robert Foss , Laurent Pinchart , Jernej Skrabec , Harry Wentland , Sam Ravnborg , Maxime Ripard , Hans Verkuil , Liam Girdwood , Paul Boddie , devicetree@vger.kernel.org, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, letux-kernel@openphoenux.org, Jonas Karlman , dri-devel@lists.freedesktop.org, Ezequiel Garcia References: <4daf0c5dbed2c47c97003ab8de0a7dbd2a335dc3.1638307601.git.hns@goldelico.com> <46070A95-0FA9-43F9-A9A9-52A7B58B88F5@goldelico.com> <58C550A4-A21E-47BA-8BAE-00B927DC7A2E@goldelico.com> <3174DA41-EB38-4C30-8752-0D9C894C74A7@goldelico.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="06/7sdeAneQqaZKj" Content-Disposition: inline In-Reply-To: <3174DA41-EB38-4C30-8752-0D9C894C74A7@goldelico.com> X-Cookie: All true wisdom is found on T-shirts. X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Paul Boddie , Geert Uytterhoeven , Neil Armstrong , David Airlie , dri-devel@lists.freedesktop.org, linux-mips@vger.kernel.org, Paul Cercueil , Laurent Pinchart , Miquel Raynal , Sam Ravnborg , Jernej Skrabec , devicetree@vger.kernel.org, Kees Cook , Jonas Karlman , Rob Herring , Maxime Ripard , letux-kernel@openphoenux.org, Ezequiel Garcia , Thomas Bogendoerfer , Liam Girdwood , Robert Foss , linux-kernel@vger.kernel.org, "Eric W. Biederman" , Hans Verkuil Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" --06/7sdeAneQqaZKj Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Dec 01, 2021 at 05:53:03PM +0100, H. Nikolaus Schaller wrote: > > Am 01.12.2021 um 16:10 schrieb Mark Brown : > > Again, if the supply can be physically absent that is a sensible use > > case but that means completely absent, not just not software > > controllable. We can represent fixed voltage regulators just fine. > The question may be how we can know for a more generic driver that there is always a regulator. > In the present case we know the schematics but it is just one example. The datasheet will generally explicitly call out if a supply can be disconnected. In general it is astonishingly rare for this to be the case, supporting that case will tend to make designing the chip harder (you have to cope with what happens where the power domains meet) and results in whatever functionality the supplies power not working. If not otherwise specified it's safer to assume that the supplies must be connected. --06/7sdeAneQqaZKj Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmGnqq0ACgkQJNaLcl1U h9AiKgf6A1p3c1dtOyuPYAkfziLEMTL656L/Ng0sT/e9yjZ9D6KPZxQqSYqZJI2F AxQcNhi9BBM7R94mawqJ6jekuZZ0RJoVo2iPJYWJ/vM36tq01U1SeojIamTmD1LN IF4vSf9paAEB6kQGTW1WB9onUyNpaIyz358HSRZ6FzxP/9W1qVhuCgw2M16JPM5G wFd64VVU8pyBLxa8glflmm8MGFaeKBqkNFJBSnRG2kX79RRtaVeX8wN6niXIsGQp T7Uv+fFGAT+w315hhRUx10oTaZNghDPE6dYLm6SaV4fqYqhIFspHZ9GsOLPvDDvC E4+8AFtE7h0IearW001RSgvJHmQFiw== =8Z88 -----END PGP SIGNATURE----- --06/7sdeAneQqaZKj--